Drill bit



1943- E. B. WILLIAMS, JR I v 2,326,908

DRILL BIT Filed May 29, 1942 INVENTOR.

Edward. BM illiamsJr. I

Patented Aug. 17, 1943 UNITED STATES PATENT OFFICE DRILL BIT Edward B. Williams, Jr., Greenville, Tex. Application May 29, 1942, Serial No. 444,955 3 Claims. (01. 255-72) This invention relates to well drilling tools and particularly to drill bits and in such connection it has more specific reference to the novel construction and arrangement thereof.

The primary object of the invention is to provide a drill bit-constructed in sections or segments so that the cutting parts of the bit may be removed and repairs made in the field when required. 7

Another object of the invention is the provisionof a drill bit constructed of a plurality of removable segments and wherein the segments are interlocked one with another and are interchangeable.

The invention also includes such features as novel means for securing the segments to a drill head, and the elimination of reaming, all of which I will'b'e clearly understood from a perusal of the following-detailed description, taken in connection with the accompanying drawing, and in the drawing:

Figure 1 is a side view of a drill head, partly broken'away and partly in section, and illustrating an embodiment of the segment bit;

Figure 2 is a top plan view thereof; the view being partly broken away;

Figure 3 is a rspective view of one of the segments showing the bottom thereof;

Figure 4 is a View similar to Figure 3, but showing the upper portion of the segment; and

' Figure 5 is a top plan view of one of thesegments, the broken lines indicating the means for securing the segments in position.

Having a more detailed reference to the drawing, i denotes a drill head with threaded portion 2 for connecting the head to a drill body. Formed on andfspaced around the head I are a plurality of ta red keys 3 for receiving and holding theme the segments for cutting. The segments show, at 4 in the several views of the drawing carry the abrasives such as diamonds of various grades, size and types, or steel alloys cast in the segments and indicated at A. The primary object of .the invention resides in the adaptability of the bit to be repaired in the field thus saving time, labor and cost. Toward this objective and as illustrated in the drawing each of the segments 4 has a recess 5 which conforms to the tapered form of the keys 3, and the keys 3 are bored at 3-11 to receive screw bolts or pins 6. This formgof construction and arrangement of the keys and segments provides a practical and effective means for holding the segments in position as the more pressure is, had on the segments the tighter the same are held on the keys.

This also prevents the segments from becoming dislodged or dropping off the keys when the drill Another important and particular feature of the drill bit is the manner of interlocking each segment with its adjacent segment. a For this purpose each segment has a tongue or projecting portion 1 and its opposite end is forked or has the projecting spaced parts 8. These parts thus interlock, the tonguesfitting snugly in between the parts 8 as shown in Figure 2 and which prevents drill fiuid from flowing in between the parts. ,7

From the foregoing it will be apparent that the drill core bit with its removable, interchangeable and interlocking segments and the manner of mounting and removing them provides a practical and useful bit of this nature. After drilling there is no reaming necessary as the hole will be cut full gauge, as, due to the segments being circular in form, in drilling the bit will slightly increase the diameter of the hole, and at the same time drill a perfectly circular hole. In case one portion of the bit becomes worn, the worn part can be removed and replaced with reinforced segments on the site, thus saving the usefulness and value in the unworn parts and thus cutting down cost of bits and drilling costs. The abrasives can thus also be removed and replaced with other segments, or adjusted on the site to meet'any drilling contingency arising in cutting the formations.

While the disclosure presents a practical working embodiment of a drill core bit embracing the features and advantages pointed out, it will be understood that the invention is not limited to the precise construction here shown, but is capable of some modifications and alterations in keeping with the inventive thought, and such as would be within the scope and meaning of the I following claims.

What is claimed is:

1. A drill core bit comprisinga hollow cylindrical head with a plurality of projecting tapered and arcuate keys spaced apart on one end of the head, a plurality of segments of arcuate form, each of which has a recess for complementally receiving the keys, each of the segments including tongue and groove means for connecting and interlocking the segments in a continuous rim on the head, the outer faces of the segments carrying abrasive elements.

2. A drill core bit comprising a hollow cylindrical head, one end of the head being threaded tongue of substantially wedge shape on one end thereof and a forked formation on its opposite end, the tongue and the forked formation projecting beyond the abrasive-holding portion of the segment, the tongue being complementally receivable in between the forked formation to thereby interlock the segments in position on the'head and upon the projections, and means for securing the segments in said interlocked po- 10 sition on the head.

EDWARD B. WILLIAMS, JR. 

